Polarity reversing switch



Feb. 26, 1952 3 Sheets-Sheet 1 Filed April 26, 1947 INVENTORS D R ma w N R R 9m WM 7 -m A .u. 0 I J M/ V. T B

Feb. 26, 1952 J, w, LAWSON ET AL 2,587,178

POLARITY REVERSING SWITCH Filed April 26, 1947 I S SheetS-Sheei 2 34 ll Mm Jon ML/iwqou mi BY Ml/I'AM t'A/n. .BRfoWMI] mm- A'rroR/ws'vs Feb. 26, 1952 J. w. LAWSON ET AL 2,587,178

POLARITY REVERSING SWITCH Filed April 26, 1947 v a Sheets-Sheet :s

INVENTORS Jo/wv W LAwsau AND BY Will/AM am BROWN M v ylv Thlir IATTORNEYS Patented Feb. 26, 1952 POLARITY REVERSING SWITCH John W. Lawson derson, Ind., poration, ware and William Earl Brown, Anassignors to General Motors Cor- Detroit, Mich., a corporation oi Dela- Application April 26, 1947, Serial No. 744,240 10 Claims. (Cl. 200-7) This invention relates to improvements in electric switches of the rotary type, and more particularly to the mechanical construction thereof.

Electric switches of the rotary type are used in installations of a character wherein the unidirectional flow of current in the ignition circuit, especially through the timer contacts, tends to cause pitting of the contacts. This unidirectional fiow of current through the contacts is quite objectionable with the result that the contacts become pitted within a relatively short time thereby necessitating replacement.

One object of the present invention is to provide a rotary switch with mechanism for counteracting the aforementioned tendency and for changing the current flow through the timer contacts each time the switch is moved to its closed position in order that the pitting of the timer contacts is reduced to a minimum.

Another object of the present invention is to provide a rotary switch of the foregoing described character which is simple in construction, dura- Me in use, eflicient and positive in operation, and economical in manufacture.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawing, wherein a preferred embodiment of the present invention is clearly shown.

A In the drawings:

Fig. 1 is a front view of the switch embodying the present invention.

Fig. 2 is a side view of the switch.

Fig. 3 is a rear view of the switch.

Fig. 4 is a diagrammatic plan of a conventional ignition system with the switch included therein.

Fig. 5 is a sectional view taken on line 55 of Fig. 1, but on a larger scale.

Fig. 6 is a sectional view taken on line 6-45 of Fig. 5.

Fig. 7 is a fragmentary detail view in elevation of the casing for the switch.

Fig. 8 is a sectional view of the casing taken on the line 8-8 of Fig. 7.

Fig. 9 is a view looking in the direction of the arrow 9 in Fig. 8.

Fig. 10 is a detail view in elevation, of the rear of one of the contact supports.

Fig. 11 is a detail view in elevation, of the front of the contact support shown in Fig. 10.

Fig. 12 is a sectional view taken on line l2-l2 of Fig. 10.

Fig. 13 is a side view of the Figs. 10 and 11.

Figs. 14 and 15 are sectional views taken on support shown in .a series of ratchet teeth 42 thereon.

teeth. The inner support 21 lines I 4--| 4 and l5l5, respectively, of Figs. 11 and 10 respectively.

Fig. 16 is a detail view in elevation of the front of another contact support.

Fig. 17 is a sectional view taken on line Ill l 01' Fig. 16.

Fig. 18 is a detail view in elevation of the rear of the support shown in Fig. 16, and looking in the direction of the arrow I8 in Fig. 17.

Fig. 19 is a sectional view taken on line 19-!!! of Fig. 16.

Figs. 20, 21, and 22 are sectional views taken on lines 20-20, 2l-2I, and 22-22, respectively, of Fig. 16.

132g. 23 is a detail view in elevation, of a ratchet p a. e.

Fig. 24 is a side view of the ratchet plate shown in Fig. 23. I

Referring to the drawings, 20 designates a tubular casing or body having a shank or boss 2 i. The body is counterbored to provide internal shoulders 22, 23 and 24. The shoulder 23, in this instance, is provided with three ratchet teeth 25 spaced apart. One end of the body 20. between the shoulders 22 and 23, provides a housing for a rotatable outer contact support or carrier 26 and a rotatable inner contact support or carrier 21. The outer face of the contact support 26 carries three contacts, 28, 29 and 30 each having two contact buttons and two tangs received by respective sockets 3|, see Fig. 16, provided by the carrier 26. This contact support is also provided with sockets 32 between each pair of sockets 3|. The sockets 32 provide seats for springs 33 which urge the contacts 28, 29 and 30 toward a switch cover or stationary contact support 34 retained on the shoulder 22 of the body 20 by bending portions or tangs of the body inwardly, as at 35. over and against the support 34.

Before the support 34 is fixed to the housing the rotatable inner contact support 21 is assembled with the outer contact support 26. The outer support 26 is provided with a counterbored opening 40 to provide an annular shoulder 4| having In this with six is rotatably and opening 40. The is provided with a reduced'portion 43 a shoulder 44. The reduced portion 43 is received by the smaller diameter of the open ing 40a. The inner support 21 is provided with a recess 45 of one face thereof and has three radial notches 46 extending from the inner walls of the recess 45 to the periphery of the support and a pair of diametrically opposite recesses 41.

instance the shoulder 41 is provided longitudinally supported in the support 21 to provide ass'm're 3 The recess" receives a metal ratchet plate ll having a list central portion which is housed within the recess II, and three relatively narrow portions or arms ll which extend outwardly in substantially radial directions irom the not portion and the tree ends are bent axially out or the plane oi the iiat portion. The tree ends or the arms cooperate with the teeth I! on the shoulder ii to provide a one-way drive connection for the carrier N by the carrier 21. A contact or bridging member ll having three contact buttons II and two arms II, see Fig. 6, which are received by the recesses l'l. The-ratchet plate ll is urged toward the bottom or the recess ll so that the tree ends the arms engage the ratchet teeth and the contact I! is urged toward the cover ll 4 is in its second "oi!" position and cannot be moved to "on" position until the key is inserted to remove the keeper from the slot ll. It is pointed out here that when the lock cylinder as assembled with the boss stop provisions are provided between the cylinder and the boss to limit the angle of rotation of the cylinder to 120', thus the cylinder cannot rotate beyond the two "0!" positions when the key is in the cylinder and is manipulated to turn the cylinder.

Since the present invention resides more particularly in the switch structure for changing the polarity each time the lock cylinder is actuated by a compression spring I! disposed between the plate ll and the contact ll.

The contact support I1 is provided with three projections or lugs II which cooperate with three detents It in the cover It to hold the support in various positions. The/support is urged toward the cover by a compression spring l'l havingone and resting on the'shoulder It and having the other end engagin the support 21.

The cover It carries stationary contacts arranged into two concentric rows, the outer rows including head rivets Iii, ll. 0!, t8 and M and the inner row comprising head rivets it, it and I1. The heads oi the rivets are preierabLv flush with the inner face or the cover. The shanks oi the rivets l, Ii, 04 and t1 project beyond the outer face oi the cover and extend through apertures provided in respective conducting straps "a, tie. a. and l'lu, while the outer ends or rivets "and I. are connected to a conductingstrap II and the outer ends or the rivets II and II are connected to a conducting strap Ii.

The switch, as thus far described is particularly used in an ignition circuit of an internal combustion engine. and is so mounted and connected with respect to the timer contact that each time the ignition circuit is closed the direction of flow 01' current through the timer contact will be reversed.

Referring to the wiring diagram, Fig. 4, the stationary contact I is connected by a lead I2 with an ignition coil II grounded at 14. The contact Ii is connected by a lead 1! with a contact 11 ot a timer II which periodically engages contact II. Contact II is connected to the contact I4 by a lead II. I One or the other of contacts 11, It is movable. A storage battery is grounded at one terminal and the other terminal is connected with the contact l1 by a wire it. The contacts I! and I! may be connected to any suitable electrical devices it desired.

The boss Ii 01 the body 2. receives a tumbler lock cylinder 85 operable by a suitable key It. The cylinder 85 also carries a handle 81 to turn the cylinder It from an oil to an "on position or vice versa. Referring to Fig. '1, the

boss is provided with cylindrical bearing surface II in which the outer surface of the lock cylinder tits and is rotated in the conventional manner. The boss II is also provided with arcuate slots I! and II into which a keeper provided by the lock cylinder may project and reciprocate as the key II is inserted or withdrawn from the tumbler cylinder.

When the keeper of the lock cylinder is in the slot is the cylinder can be rotated 60 irom the "oil!" to "on? position by the handle, but when the keeper is in the slot II the lock cylinder from the "oil" position to the "on" position further description or the locking cylinder is deemed unnecessary.

When ignition is required the lock cylinder is turned from the "of!" position to the "on" position to drive the contact support ll. For this purpose the rear end or the lock cylinder is provided with a non-circular lug liiii that projects into a complementary recess ill provided by the support. The lock cylinder is also provided with a recess I02 which receives an extension ill formed on the carrier 21.

When the back cylinder is actuated in a counterclockwise direction, as viewed in Fig. i.

it will drive the support It in a counterclockwisedirection because the free ends of ilngers l. or plate is cooperate with the teeth 42 of the support "to drive the support 26, and alter a predetermined angular distance the proiection II will enter into the detents II. In this way the movable contact carrier 11 of the switch will be yieldingly maintained in various positions. When it is desired to move the switch from "on to ."oil" position, the lock cylinder can be moved in either clockwise or counterclockwise direction. When the lock cylinder is moved in the clockwise direz timi fingers ll will slide over teeth 41. but the support 28 is prevented from turning in the clockwise direction because extensions I",

Jormed on one side of support, see Fig. 18, abut minimum of contact pitting. When the switch is in its closed position as shown in Fig. 4, the path oi current from the storage battery will be a follows. Current will flow from the positive side of the battery 8| through lead I! to contact 81. bridging member 50. strap "II, contact 03, contact 30. contact ll through lead wire III to contact is, contact 11, lead wire 15, contacts hi. and I0, and thence through coil II to grmnnii ll. When handie or key reverses its move it in the clockwise direction to the 011" position. the contacts 20, 29 and 30 will remain in the positions illustrated, but the the bridging member will be moved in a clockwise direction to ofl" position. This condition exists due to the f act that the teeth 2! prevent the support 26 from moving in the reverse direction, but when the switch is again moved to the "on" position the support through the plate ll drives the support 28 thus changing the position or the contacts 28, 29 and 30, causing the contact 28 to bridge contacts -42, and

' contact III to bridge contacts "-60. This will be contact ll, strap '10, contacts I2, 28, ll, lead ll, contact I1, contact 18, lead 80, contacts 84, 30, '0 and thence through coil to ground 16.

In this above construction of the switch it will be noted the switch has two ofl" positions and one on position and it is possible to. manipulate the switch from oil to on" posi tion by the handle without the use of a key. In order to do this, the operator inserts the key in the lock cylinder causing the keeper to be within the cylinder. Then the cylinder is rotated to "on" position and then the key can be removed causing the keeper to lie in the groove 90 after which the handle can move the cylinder to "off" position and then to on position. It is pointed out that on each movement of the lock cylinder to on position when the keeper is in groove 90 the support 28 will drive the support 21 60 to change the position of the contacts 28, 28, and 30. In case the operator desires to lock the switch so that it cannot be manipulated to on" position by the handle the operator inserts the key in the cylinder and thenlmoves the lock cylinder in the off position which will permit the keeper provided by the lock cylinder to register with the groove 9| and then remove the key. In this position when the key is removed the keeper will automatically move the lock cylinder into the groove 9| therefore the lock cylinder cannot be rotated by the handle 81 in the reverse direction to the on position without first inserting the key to free the keeper of the groove 9 l.

While the embodiment of the present invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, and although the description limits the switch to the reversal of the polarity of ignition timer contacts it is to be understood the switch may be used for other purposes requiring a reversing or circuit selecting switch, all coming within the scope oi the claims which iollow.

What is claimed is as follows:

1. An electric switch comprising in combination; a housing; a closure for the housing supporting two circular rows of stationary contacts; a pair of concentric rotors mounted for axial and angular movements respective to each other Within the housing the outer rotor supporting a plurality of biased contacts each contact capable of bridging a pair of the outer row of conon the support and the inner rotor supportin a yieldable contact capable 01' bridging all of the stationary contacts or the inner row of contacts simultaneously; ratchet provisions between the rotors whereby both rotors move to gather in one direction of rotation only; ratchet provision between the outer rotor and the housing to prevent reverse movement of the outer rotor upon reverse movement of the inner rotor; means for actuating the inner rotor in either direction of rotation; spring means for urging the inner rotor against the closure; and means for maintaining the inner rotor in various positions, said means including arms formed integral with inner rotor capable of extending into recesses provided by the closure.

2. An electric switch comprising in combination; a cup-shaped casing; a pair of concentric contact carriers, one supported within the other and adapted for angular and axial movements with respect to each other within the casing; ratchet provisions between the carriers whereby both carriers turn together in one direction of rotation, said provisions permitting the inner carrier to move in the opposite direction of rotation relative to the outer carrier; ratchet provisions between the outer carrier and the bottom of the casing for preventing reverse rotation of the outer carrier upon reverse movement of the. inner carrier; means for actuating the inner carrier in either direction of rotation; and means for limiting the angular movements of the inner carrier whereby the inner member must be reversed a certain angular distance before the ratchet provisions between the carriers is operative to actuate the outer-carrier further, in its angular movement. Y I a 3. An' electric switch comprising in :combination; a cup-shaped casing having a series 01' ratchet teeth in the bottom of the casing; a pair 01' concentric contact carriers mounted for angular movements within the casing, one 01' said carriers being arranged for step-bystep ments in one direction of rotation only while the other carrier is mounted for oscillating movements on either side of a medial position; ratchet provisions between the carriers whereby both carriers move together in said one direction only; extensions provided by the first mentioned carrier and cooperating with the ratchet teeth on thebottom oi the casing for preventing reverse movement of the first mentioned carrier upon reverse movement of the other carrier; key control means for actuating the carrier capable oi oscillating movements; and means for limiting angular movement of the actuating means on each side of the medial position, the angular movement of the actuating means being from one side position while a key is inserted in the actuating means to the other side position, the rotating movement of said actuating means being limited from one side position to the medial position when the key is removed and when the key is inserted the rotating movement can be extended from the medial position to the other side position said movement causes the first mentioned carrier to turn step-by-step in said one direction said actuating means being nonrotatable for operation of the oscillatable carrier upon removal of the key when the elements are in the other side position.

a. An electric switch comprising in combination; a cup-shaped casing having a series of ratchet teeth; a closure for the casing supporting two circular rows of stationary contacts; means for connecting contacts 01' one row with contacts of the other row; a pair of concentric rotors located within the casing and capable of moving axially and angularly relative to each other, said outer rotor having inner ratchet teeth; slidable circuit closing means carried by each rotor; spring means supported within each rotor for urging same and their respective circuit closing means apart; a plate supported by the inner rotor and having arms extending through notches, the free ends of the arms cooperating with the inner ratchet teeth of the outer rotor to drive same in one direction of rotation; spring means for urging the inner rotor toward the closure; cooperating means provided by the inner rotor and the closure to maintain yieldingly the inner rotor in various positions; means for driving the inner rotor in either direction of rotation; and extensions on the outside of the outer rotor adapted to cooperate with the ratchet teeth on the casing to prevent reverse movement of the outer rotor upon reverse movement of the inner rotor.

5. An electric switch comprising in combinamove- 1 tion; a casing; a closure for the casing supporting two concentric circular rows of stationary contacts; means to: connecting at least tvai con. tacts of each row together; a pair oi concentric rotors located within the casing; a. pluraiity oi biased contacts carried by the outer rotor int 211- gaging a pair 01' contacts on the outer in stationary contacts; biased bridge means 11 by th inner rotor for engaging all or n row of contacts simultaneousiy; means for per odically causing the rotors to move reciproca in the longitudinal direction. as they a. in one direction whiie simulta' eously' res lair the outer rotor from rotating. in the opposite or rection, said means comprising a biased plate having radial arms slidablv supported. in .otcheo provided by the inner rot uooperutinu with tioned on one side oi the o rotor wherehy when the arms come in cont with ti shout de 4: rotors rotate together and ezcte the other side oi the outer r ate with tapered cams havir abrupt c oulders positioned within the case whereby when the ewetensions come in contact with the shoulders on the case on the reverse movement of the inner rotor the movement of the outer rotor is stopped; and means for actuating the inner rotor.

6. An electric switch comprising in combina tion; a casing having parallel walls, one oil which is provided with two circular rows of stationary contacts; a pair 01' concentric rotors mounted for rotation within the casing; an oscillatable driving member supported by the other wall or driving the inner rotor in either direction of rotation; bridging members yieldingly and slidably supported by each rotor for engagement with the stationary contacts; a one-way driving connection between the rotors; cooperating means pro vided by the inner rotor and first mentioned wall and cooperating to maintain yleldingly the inner rotor in various positions; and ratchet provisions provided by the other wall and the outer rotor operating to prevent reverse movement 01' the outer rotor upon reverse movement or the driving member and inner rotor.

7. An electric switch comprising in combination; a casing having parallel walls, one'of which is provided with two circular rows of stationary contacts and the other with ratchet teeth; a pair of concentric rotors mounted for rotation within the casing, said outer rotor having inner and outer ratchet teeth with outer ratchet teeth cooperating with the ratchet teeth on the wall of the casing to prevent rotation of outer rotor in one direction of rotation; bridging members yieldingly supported by each rotor and arranged to engage the stationary contacts: a plate having arms carried by the inner rotor, said arms cooperating with the inner ratchet teeth 01' the outer rotor to drive same in one direction of rotation; cooperating means provided by the inner rotor and one wall of the casing to maintain the inner rotor in various positions; and means for driving the inner rotor in either direction of rotation.

8. An electric switch comprising in combination; a cup-shaped casing;. a closure for the casing supporting two circular rows of stationary contacts; means for connecting contacts of one row with contacts of the other row; a pair of concentric roinri'. mounted for axial and angular movements within the casing; said outer rotor having inner ratchet teeth and said inner rotor having projections; biased circuit closing means carried by each rotor; a plate supported within the inner rotor and having arms extending through notches provided by the inner rotor with the free ends cooperating with the inner ratchet teeth of the outer rotor to drive same in one direction. or rotation, spring means for urging the inner rotor toward the closure to urge the projection. into recesses provided by the closure to maintain yieldingiy the inner rotor in various rmsitions; means for driving the inner rotor in either direction of rotation; and ratchet provisions provided between the outer rotor and the housing to prevent reverse movement or the outer rotor upon reverse movement of the inner rotor.

9.. An electric switch comprising in combination; a casing; a pair of concentric contact carriers, one supported within the other and adapted for angular and axial movements with respect to each other within the casing; ratchet provisions between the carriers whereby both carriers rotate together'in steps in one direction of rotation, said provisions permitting the inner carrier to rotate in opposite directions; ratchet provisions between the outer carrier and the casing for preventing same from turning in the opposite direction upon reverse movement of the inner carrier; means for actuating the inner carrier in either direction of rotation; and means for limiting the angular movements of the inner carrier to a certain number of steps in either direction oi rotation and whereby the inner member must be reversed at least one step before the ratchet provision between the carriers is operative to operate the outer carrier another step in the movement of steps.

10. An electric switch comprising in combination; a casing; an oscillatable contact carrier and a rotatable contact carrier supported and adapted for angular and axial movement within the casing; ratchet provisions between the carriers whereby both carriers rotate at the same time. said provisions permitting the oscillatable carrier to move in opposite directions of rotation; ratchet provisions between rotatable carrier and the easing for preventing reverse rotation of the same upon reverse movement of the oscillatable carrier; means for actuating the oscillatable carrier; and means for limiting the angular movements of the osclllatable carrier in the direction to rotate the rotatable carrier so that the osclllatable carrier must be reversed a certain angular distance before the ratchet provision between the carrier is effective to turn the rotatable carrier.

JOHN W. LAWSON. WILLIAM EARL BROWN.

REFERENCES CITED The following references are 01' record in the 

